<!doctype html>
<html>
<head>
    <meta charset="UTF-8">
    <title>test</title>
    <style>
        body{
            background-color: #a8a8a8;
        }
        div{
            background-color: #fff;
            padding: 2em;
        }
        p{
            margin: 0;
        }
        
        p~p{
            border-top: 1px dashed #ccc;
            margin-top: 1em;
            padding-top: 1em;
        }
    </style>
</head>
<body>
    
    <div>
        
    <p>
        <span>哈哈：</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
    </p>
    <p>
        <span>哈哈：</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
            <span>哈哈哈哈</span>
    </p>
    </div>
    
</body>
</html>